In a variety of applications, an electrical cable must be towed or otherwise subjected to a pulling force. In such situations, it is desirable that the pulling force not be transmitted to the electrical wires or connection points. One such application is underwater seismic cables. In order to accommodate the pulling forces, which can be quite great, such cables are traditionally sheathed in an armouring layer comprising high tensile strength wires or the like integrated into the armouring. This armouring layer takes up the pulling forces, thus protecting the electrical wires from damage. The armouring layer also protects the electrical wires from damage due to abrasion against the seafloor while the cable is towed/deployed.
A seismic cable is, however, comprised of several modules housing electronic measuring apparatus joined in series by segments of the above-described, reinforced electrical cable. The cable segments have plugs at their ends, which are plugged into each end of the modules. This permits, among other things, intermediate modules in the series to be unplugged and replaced as needed. As can be appreciated, it is undesirable for the plug connection themselves to be subjected to the pulling forces. In order to prevent this, a transitional sleeve device may be bolted at its first end to the module, with its second end being connected to a coupling that is securely affixed to the reinforced armour of the cable. Since the pulling forces are transmitted from the module, via the sleeve, to the insulation layer, a slightly longer segment of exposed cable passing inside the sleeve and plugged into the module will not be subject to pulling forces. Because seismic cables are typically wound up and/or deployed from drums turned by winches onboard the seismic vessel, the sleeves must be flexible enough to negotiate the turn of the drum, as well as being resilient and durable enough to withstand to very great pulling forces and the harsh underwater environment. As a result, prior art transition devices have been large, cumbersome, complicated to assemble, and expensive, as well as having other disadvantages known to those skilled in the art. There is a need therefore, for an improved transitional device for connecting segments of seismic cable to intermediate sensor modules that can tolerate the unique and harsh environment where seismic cables are utilized.